The Nervous System

Central Nervous System (CNS)

The part of the nervous system that consists of the brain and spinal cord. Integrating and command center. Interprets incoming sensory info and issues instructions on how to respond based on past experiences and current conditions.

Peripheral Nervous System (PNS)

The part of the nervous system outside the brain and spinal cord. Links all parts in the body, consisting of nerves nerves that extend from the brain and the spinal cord. Spinal nerves carry impulses to and from the spinal cord and cranial nerves carry impulses to and from the brain.

Somatic Nervous System

often called the voluntary nervous system because we consciously control most of the skeletal muscles with the exceptions of reflexes

Autonomic Nervous System

called the involuntary nervous system because it regulates smooth muscle, cardiac muscle, and glands

Sympathetic Division

a part of the autonomic nervous system that prepares the body for stress-related activities, often referred to as the "fight or flight" response.

Parasympathetic Division

a part of the autonomic nervous system that promotes rest and digestion, often referred to as the "rest and digest" response.

Afferent Division

the part of the nervous system that transmits sensory information from the body to the central nervous system.

Efferent Division

the part of the nervous system that carries motor commands from the central nervous system to the muscles and glands.

Homeostasis

the state of steady internal, physical, and chemical conditions maintained by living systems.

Cerebrum

the largest part of the brain, responsible for higher brain functions such as thought, action, and sensory processing.

Brain

the central organ of the nervous system, controlling thought, memory, emotion, touch, vision, breathing, and many other functions.

Thalamus

a brain structure that acts as a relay station for sensory information and plays a role in regulating sleep and alertness.

Hypothalamus

a small region of the brain located below the thalamus, responsible for regulating many essential functions such as hunger, thirst, body temperature, and circadian rhythms.

Epithalamus

a portion of the brain located near the thalamus, involved in the regulation of sleep-wake cycles and emotional responses. Usually represented by Pineal gland

Diencephalon

the part of the brain that includes the thalamus, hypothalamus, and epithalamus, playing a crucial role in sensory processing and homeostasis.

Pineal Gland

a small endocrine gland in the brain that produces melatonin, regulating sleep patterns and circadian rhythms.

Brain Stem

the lower extension of the brain that connects to the spinal cord, responsible for regulating vital functions such as breathing, heart rate, and blood pressure.

Cerebellum

the part of the brain located at the back, responsible for coordination, balance, and fine motor control.

Medulla Oblongata

the part of the brain stem that controls autonomic functions such as heart rate, respiratory rate, and reflexes.

Meninges

the three protective membranes covering the brain and spinal cord, consisting of the dura mater, arachnoid mater, and pia mater.

Cerebrospinal fluid

a clear fluid that surrounds and cushions the brain and spinal cord, providing protection and nutrients.

Spinal cord

Neurons

Dendrites